What do I notice about this?

You can receive a notification about the new certificate on your mobile device (telephone or laptop). This depends on the brand of your device. Apple users in particular will notice this via a pop-up shown on the device. Do you see the above message or a similar message? You can then indicate that you trust the certificate. With this you accept the new certificate and you can use eduroam again. You only need to do this once.

Not trusted

Although the notification states that the certificate is not trusted, you can accept the certificate. The certificate is safe, but because (the organization) Apple does not know this certificate itself, Apple marks it as “unsafe”.